1. Field of the Invention
The present invention relates to a tensile exercising device and, more particularly, to a portable exercising device which may be extended during use by a person in order to provide elastic resistance, thereby developing muscle strength.
2. Discussion of Related Technology
Many elastic exercising devices have been developed which can stretched, pulled or extended by a user in order to develop and maintain body muscles. Often, these devices use a series of tightly coiled springs having handles attached at opposite ends. When the handles are pulled apart, the spring is extended and provides resistance, which is overcome by the force produced by the person utilizing the exercising device. The springs are stretched and relaxed repeatedly during a single exercising session. There are several drawbacks of spring-based devices: they are heavy, difficult to store and transport; they present an unappealing, mechanical appearance; and they are uncomfortable when brought into contact with the human body. Furthermore, because of the mechanical nature of the device, construction tends to be complicated.
In addition, the handles of such devices must be made of a relatively rigid material in order to properly interface with the other mechanical portions of the device. These rigid handles become slippery due to perspiration and make it difficult for the user to maintain a constant and secure grip on the apparatus. If the grip is lost when the springs are in an extended position, injury to the user and damage to the equipment may result.
Other tensile exercising devices use rubber or other elastic materials which have handles fastened at opposite ends. While such devices are generally more portable than spring-based devices, the handles are still typically made of a rigid material in order to facilitate attachment, with the accompanying problems in maintaining a proper grip noted above. Alternatively, the handles are an integral portion of the complete device, so that when the handle fails or develops a defect, the entire unit must be replaced. Also, both the rigid handles and handles formed from loops of material tend to be uncomfortable to the user, and do not allow the user to exercise the muscles in the lower arms, hands, and fingers.
Another problem common to previous tensile exercising devices is the inability to conveniently adjust either the amount of elastic resistance or the size of the handles according to the size and strength of the user. Typically, these devices are either difficult for a beginner to use, or easily manipulated by a person already possessing well-developed muscles, thereby minimizing the beneficial effect of the device. Further, the previous devices do not allow the user to conveniently adjust the length of the device according to the user's size and the exercise to be performed.